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Social security contributions comparison in Sisseln explained simply

Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on social security contributions in Sisseln: what the law requires, what can be automated, and when to delegate.

The Swiss legal frame for social security contributions

For an owner in Sisseln, the question is never “do we need accounts?” but “at what level of detail?”. The CO sets the floor; the bank, the tax office and the shareholders set the rest.

Late books show from the outside: poorly calibrated tax instalments, provisional filings, slow answers to the bank. Staying current is also a matter of image.

A Swiss SME's accounting calendar

Three families of deadlines shape the year: federal (VAT within 60 days, salary declaration in January), cantonal (tax return, extensions depending on the canton, including in Sisseln) and internal (closing, general meeting within six months). Mixing them up is the leading cause of delays.

For social security contributions, two dates lock themselves in every year: the January salary declaration and the general meeting within six months — everything else is planned around them.

Digitalising social security contributions: what actually works

Security is part of digitalisation: named access, tested backups, encryption of sensitive data. A digital accounting file is protected like a safe — because it is one.

For an SME in Sisseln, the real gain of digitalised social security contributions shows day to day: no paper pile at month-end, VAT prepared continuously, and an owner reading today's figures rather than last quarter's.

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Salaries and social contributions: the rates to know

Two of these contributions are set by law: AHV/IV/APG at 5.3% and unemployment at 1.1%, both payable by the employer. The others — LPP, accident insurance, possibly daily sickness benefits and family allowances — depend on the insurer, the industry and the pension plan. The total surcharge usually falls between 12 and 20% of gross pay, and employee deductions between 10 and 15%: these are orders of magnitude, not statutory rates.

Withholding tax applies to foreign employees without a C permit: the employer deducts tax at the cantonal rate and remits it. The annual salary certificate remains mandatory for all staff — it is the linchpin connecting payroll accounting, tax returns and AHV audits.

Sisseln: what changes, what does not

Sole proprietorship, Sàrl or SA in Sisseln: the AHV contact remains the competent compensation office, and taxes follow the scales of the canton Aargau.

For a business in Sisseln, that means VAT returns identical to anywhere in Switzerland, but a tax return and family allowances governed by the canton Aargau.

Frequently asked questions

What are the legal obligations for social security contributions in Switzerland?

The foundation is the Code of Obligations: proper bookkeeping (art. 957a CO), annual accounts (balance sheet, income statement, notes) and 10-year retention of books and records (art. 958f CO). VAT applies from CHF 100,000 of turnover, and social insurance settlements from the first employee. Nothing is different in Sisseln: federal law applies.

Does MyFiducia.ai work for a business based in Sisseln?

Yes: the platform runs online, the rules applied are federal (VAT, CO, AHV), and the file can be shared with any fiduciary. A business in Sisseln manages its documents, VAT and exports exactly as anywhere in Switzerland.

When is entry in the commercial register mandatory?

A Sàrl and an SA only come into existence with their registration. A sole proprietorship must register from CHF 100,000 of annual revenue; below that, registration stays voluntary but adds credibility and protects the business name. Registration goes through the canton's commercial register office — for Sisseln too.

Which documents should be prepared for the year-end closing?

Bank and cash statements at the closing date, the inventory of stock and work in progress, final AHV/LPP/accident settlements, contracts signed or amended during the year, invoices straddling two years and the detail of accruals. With an up-to-date document archive, most of it is already there. The list is identical in Sisseln: the CO dictates it, not the commune.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates social security contributions for businesses in Sisseln: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

The application is operated in French.

    Social security contributions comparison in Sisseln